ABSTRACT
AIM:To observe the effects of cholecystokinin octapeptide (CCK-8) and its receptor antagonists on cAMP response element binding protein ( CREB) and phosphorylated CREB ( pCREB) expression in frontal cortex and hippocampus of morphine withdrawal rats , which aim to explore the post-receptor mechanism through which CCK-8 regu-lates morphine withdrawal .METHODS: After the morphine dependence and naloxone-precipitated withdrawal animal models were established, the effects of CCK-8, L-364718 (CCK1 receptor antagonist) and LY-288513 (CCK2 receptor an-tagonist) pretreatment on CREB and pCREB expression in frontal cortex and hippocampus were observed by Western blot -ting and immunohistochemistry .RESULTS:In rat frontal cortex neuron , CREB was expressed in both cytoplasm and nu-cleus, but pCREB was only highly expressed in the nucleus .In the pyramidal cell layer of hippocampal CA 1 region, CREB showed high expression in the cytoplasm and low expression in the nucleus , while pCREB was only expressed in the nu-cleus.No obvious change of CREB was observed after either chronic morphine treatment or naloxone withdrawal .The pCREB expression was increased after chronic morphine treatment and further increased after naloxone withdrawal .Com-pared with the withdrawal group , chronic pretreatment with CCK-8, L-364718 and LY-288513 had no effect on CREB expression in the frontal cortex , but obviously decreased the pCREB expression .In the hippocampus , pretreatment with L-364718 and LY-288513 decreased CREB and pCREB expression , but only the pCREB expression was decreased after CCK-8 treatment.CONCLUSION:CCK-8 and CCK receptor antagonists may alleviate morphine withdrawal symptoms by regulating CREB , with specificity in different brain regions .
ABSTRACT
BACKGROUND:Establishing a characteristic.stable and repeatable model of Th1/Th2 imbalance in animals,is the key of studying the mechanism of Th1/Th2 imbalance.OBJECTIVE:To observe the characteristics of Th1/Th2 imbalance in splenocytes derived from Balb/C mice immnnized by keyhole limpet hemocyanin(KLH).DESIGN:A randomized control exploratory experiment.SETTING:Hebei Provincial Forensic Laboratory.Institute of Basic Medicine,Hebei Medical University.MATERLALS:The experiment was carried out in the Hebei Provincial Forensic Laboratory,Institute of Basic Medicine,Hebei Medical University from September 2005 to January 2007.Balb/C mice were adopted in this study.and all the disposals were in accordance with the guidance of animal ethics.METHODS:Balb/C mice were immunized with KLH emulsified in complete Freund's adjuvant(CFA),splenocytes were acquired,and the peak of cytokine secretion was determined in 3 groups:KLH groups of 6.25 mg,kg.12.5 mg,kg and 25 mg/kg.According to the immunizing dose and immunizing frequency.mice were divided into 7 groups:KLH groups of 6.25 mg/kg,12.5 mg/kg and 25 mg/kg,secondary immunity groups of 6.25 mg/kg,12.5 mg/kg and 25 mg/kg,as well as control group.According to the determined levels of IgG1 and IgG2a in blood serum.mice were divided into KLH group of 6.25 mg/kg and control group.MAIN OUTCOME MEASURES:Mice splenocytes supematant was detected with enzyme linked immunosorbent assay (ELISA)for the production of Th1 cytokines interferon (IFN)-γ,interleukin(IL)-2.IL-12 p40 and Th2 cytokines IL-4 and IL-5.The levels of Th1 antibody IgG2a and Th2 antibody IgG1 in blood serum were also detected by ELISA.RESULTS:The spleen derived from KLH-immunized mice appeared hypertrophy,and the number of splenocytes was manifold.Splenocytes restimulated with KLH in vitro produced much more IFN-γ,IL-2,IL-4,IL-5,but not IL-12p40.IL-2 secretion was obviously elevated after incubated for 24 hours and achieved pinnacle at 48 hours;productions of IL-4,IL-5 and IFN-γ were elevated after 24 hours,and increased gradually to 96 hours;IL-12p40 production was very low at every time point.Using different doses of KLH inlmunity once or twice,could all lead to the elevated productions of IL-2,IL-4,IL-5,IFN-γ,and the elevation of IL-4/IFN-γ ratio,but the secondary immunity group of 6.25 mg/kg KLH showed obviously higher levels than other groups(P＜0.01).The level of KLH specific antibody IgG2a and IgG1,especially IgG1 was elevated in blood serum of KLH-immunized mice.CONCLUSION:Balb/C mice immunizad with KLH emulsified in CFA can indce a Th2 predominant imbalance in splenocytes.
ABSTRACT
Aim To investigate the effects and mechanisms of CCK-8 on IL-1? induced proliferation of RSC-364, a rat fibroblast-like synovial cell line. Methods MTT colorimetric assay and Western blot were used to measure cell proliferation and p38MAPK phosphorylation level to elucidate the mechanism of CCK-8 in IL-1? induced RSC-364 proliferation. Results CCK-8 significantly inhibited IL-1?-induced RSC-364 proliferation at 10 -12 , 10 -10 , 10 -8 , 10 -6 mol ? L -1 , and IL-1?-activated p38MAPK activity at 10 -10 , 10 -8 , 10 -6 mol?L -1 in a dose-dependent manner. The effect of CCK-8 was blocked by CR1409 (a CCKA-receptor antagonist) and CR2945 (a CCKB-receptor antagonist). Conclusion CCK-8 inhibits IL-1?-induced RSC-364 proliferation, probably by reducing p38MAPK activity through CCKA and CCKB receptors.
ABSTRACT
Forensic toxicology is a specialized subject which forensic medical appraisers and students must learn and master. As a new teaching mode,problem based learning method is attrcting a lot of attention. Applying "case" based PBL teaching method is an important method to train innovative and high technical ability forensic talents.
ABSTRACT
Aim To investigate the effects of cholecystokinin-octopeptide on IL-12 secreted in murine bone marrow-derived dendritic cells induced by lipopolysaccharide.Methods The CCK receptor subtypes were investigated by immunofluorescence in murine bone marrow-derived dendritic cells.Enzyme linked immunosorbent assay and Western blot were used to estimate the contents of IL-12 and p38MAPK activity.Results CCK-1R and CCK-2R were detected in BM-DC;CCK-8(at concentrations of 10-10,10-8,10-6 mol?L-1)could significantly increase the secretion of IL-12 in the LPS-induced DC, and LPS-activated p38MAPK activity in a dose-dependent manner.The effect of CCK-8 was reduced partially by CR1409(a CCK-1R antagonist) and CR2945(a CCK-2R antagonist).Conclusion CCK-8 could dose-dependently increase the expressions of IL-12 in LPS-induced DC,probably by promoting p38MAPK activity and the effect was mediated by CCK1 and CCK2 receptors.
ABSTRACT
AIM: To investigate in vitro effects of cholecystokinin octapeptide(CCK-8) on the expressions of B7.1 and B7.2 and the costimulatory activity of T lymphocytes in unstimulated macrophages.METHODS: Mouse peritoneal macrophages were isolated and incubated with CCK-8(10-12-10-6 mol/L) for indicated time.The B7.1 and B7.2 expressions of murine peritoneal macrophages were analyzed by flow cytometry.CD4+T cells were isolated from mouse spleen using immunomagnetic beads,and cultured with 1/4 numbers of macrophages which were pretreated with CCK-8 and/or anti-B7.1 antibody,anti-B7.2 antibody,CCK1R antagonist CR1409,CCK2R antagonist CR2945 for 24 h.ConA was added into the culture medium to stimulate CD4+T cell proliferation.The proliferation was determined by measuring -TdR incorporation in a ?-scintillation counter.RESULTS: B7.1 and B7.2 expressions and costimulatory activity of peritoneal macrophages were enhanced by CCK-8 in a dose-dependent manner,and the maximal effects occurred at the concentrations of 10-9 mol/L to 10-7 mol/L.Anti-B7.2 antibody,but not anti-B7.1 antibody,reduced the modulatory role of CCK-8 on costimulatory activity.Both CR1409 and CR2945 reversed the effect of CCK-8 on costimulation,and the role of CR1409 was more significant.CONCLUSION: CCK-8 enhances macrophage costimulatory activity by upregulating B7.2 expression,which is mediated by CCK1R and CCK2R.CCK1R might be the major receptor responsible for the modulation of CCK-8 on costimulation.
ABSTRACT
AIM: To study the effects of cholecystokinin octapeptide (CCK-8) on T-lymphocyte subsets in keyhole limpet haemocyanin (KLH)-immunized mice.METHODS: Female BALB/c mice were immunized with KLH and injected with different dosages of CCK-8 or saline simultaneously. Positive CD4+and CD8+ T cells in peripheral blood or splenocytes were measured by flow cytometry. The production and mRNA level of Th1 cytokine, IFN-? and Th2 cytokine, IL-4 in the splenocytes were evaluated by ELISA and RT-PCR, respectively. In addition, lung tissue sections were made with HE staining.RESULTS: CCK-8 downregulated the positive CD4+and CD8+ T lymphocytes both in peripheral blood and in splenocytes in KLH-immunized mice, resulting in the reduction of CD4+/CD8+ ratio.CCK-8 improved the production of IFN-?, elevated IFN-? gene transcription, whereas cut down the production of IL-4, decreased IL-4 gene transcription. CCK-8 lightened the pulmonary inflammation induced by KLH.CONCLUSION: CCK-8 inhibits CD4+T lymphocytes activation, Th2 cytokine mRNA expression and protein production in KLH-immunized mice, indicating that CCK-8 modulates adaptive immune response.
ABSTRACT
AIM:To observe the effects of cholecystokinin octapeptide(CCK-8) on the expression of proinflammatory cytokines IL-1?,IL-6 and anti-inflammatory cytokines IL-10,IL-4 in LPS-attacked mice.METHODS: Kunming mice were randomly assigned and injected intraperitoneally with LPS alone or/and CCK-8 at different time points.The expression of IL-1?,IL-6,IL-10 and IL-4 in the serum and lung tissues were assayed by ELISA and RT-PCR.RESULTS: The expression of IL-1?,IL-6,IL-10 and IL-4 were upregulated in LPS-attacked mice.Pre-treatment of CCK-8 decreased both IL-1? and IL-6 expression and augmented IL-10 and IL-4 expression in LPS-attacked mice.CONCLUSIONS: CCK-8 exerts an anti-inflammatory effect by inhibiting the expression of IL-1?,IL-6 and increasing the expression of IL-10,IL-4 in LPS-attacked mice,which could alleviate the inflammatory response in lung tissue.